Added orientation parameter to write_videofile

[yemibox51]

Fixing Issue #1911

• I have provided code that clearly demonstrates the bug and that only works correctly when applying this fix
• I have added suitable tests demonstrating a fixed bug or new/changed feature to the test suite in tests/
• I have properly documented new or changed features in the documentation or in the docstrings

[yemibox51]

When running the tests suite, getting 23 failed tests, this was before I made any changes. Also don't know how to get the pre-commit to work with python3.9 and without updating any of the config files.

[coveralls]

Coverage: 84.513% (+0.8%) from 83.73% when pulling fdb92fa on yemibox51:yemibox51/bug_portrait-rendered-as-landscape into 858bb81 on Zulko:master.